Lubricating method and means



June 24, 1930. D. H. swEET LUBRICATING METHOD AND MEANS Filed April 27, 1925 Ssgs i under pressure to Patented June' 24, 1930 UNITED -STATES PATENT OFFICE n noNALnn. swam, or NvANs'roN, ILLINoIs,

ASSIGNOR TO ALEMITE CORPORATION,

LUBmca'rrNe METHOD AND MEANS Application filed April 27, 1925. Serial No. 26,102.

My invention relates to lubrication and more specically to an improved method and means for supplying to a part to be lubricated a predeterminedI charge 'or dose of lubricant each time a pressure impulse is received. v

Among the objects and advantages of the invention may be enumerated:

First, to provide lubricant measuring means operated by the supply of lubricant deliver a predetermined amount of lubricant on each pressure impulse.

Second, to measure lubricant automatically in response to pressure impulses, independent of the pressure or its duration or its rate of application.

Further objects and advantages of the invention will become apparent as the description proceeds.

`In the accompanying drawings:

Figure 1 is a central sectional view through an automatic measuring means according to the invention.

Figure 2 is a section of the same parts with the feeding stroke partially completed.

Figure 3 is a similar section at the end of the feeding stroke.

Figure 4 is a section on ure 2.

Figure 5 is a diagram of a simplified manually operated system.

Figure 6 is a .sectional view of a modiication.

In the embodiment, of apparatus according to the invention selected for illustration the measuring means comprises a housing 10 threaded at 12 for mounting the same on line 4-4 of Figthe stationary portion of a bearing or other machine element requiring lubrication. The casing 10 also carries a cover threaded thereto at 14, said cover having an annular shoulder 16 and a central dome 18 terminating in an inlet 2O provided with a shoulder 22 for abutment with the en'd of spring 24 holding a valve 26 in the position shown in Figure 1. A suitable coupling 28 forms a seat for the valve 26 and is threaded for connection to any suitable conduit through which lubricant under pressure may be delivered to the device.

Within the chamber I provide a movable barrier formed in two parts with a lost tion connection between the parts. This barrier functions both as a piston and as its own by-pass valve. This structure comprises a central piston proper 30 and a sleeve 32. The sleeve 32 is notched at 34 to permit lubricant to pass between itselr` and the outer wall of the casing 10, and 'rictionally held against movement in either direction by a ring 36 similar to a piston ring, but cut away at 38 to provide a clearance large enough so that at least one entire passage 34 will always be open. The sleeve is contracted at 40 to provide an external shoulder positioned to abut the shoulder 16 and. an internal shoulder to engage the top of the piston 30 and limit its upward movement. The lost motion connection between the parts is completed by a central bolt 42 carrying a cross piece 44 overlying the upper end neck 46 of the sleeve but spaced therefrom in the normal position of rest, as clearly yshown in Figure 1. The inner surface of the cap, where the shoulder 16 joins the wall of the dome 18, is beveled, as at 48, and the upper end of the neck 46 just completes a seal with the lower end of the dome 18 in the initial position of Figure 1.

A single spring 50 acts on piston 30 to press it toward the inlet, being housed'in an annular groove 52 in the piston to Veconomize in overall dimensions. The piston 30 terminates at its discharge end in an eXtension 54 adapted to enter the exit 56 and seal the same. y

The operation of the lows:

Upon the delivery of check valve 26 will open,

structure is as fola pressure impulse as 1n Figure 2, and

pressure will be exerted in the first instance against piston 30 causing it to move down to the position shown in Figure 2. During this movement sleeve 32 remains stationary, partly due to friction, but also because the hydraulic pressure of the nulus 40 tends to force (the piston and sleeve discharge on the anaway from each other. During this movement the entire charge or dose of lubriant -is expelled, being represented by a volume equal to the entire area of piston 3() multi- 5 plied by the distance moved between the position of Figure 1 andthat of Figure 2.

At this point extension 54 forms a seal with exist 56 to'prevent further discharge of lubricant. The cross piece 44 also mechanically engages neck 46, so that the ressure impulse will force both sleeve an piston to move asa unit down to the position of Figure 3. This movement carries extension 54 into the exit 56, and opens communication at the upper end of the neck 46 and over shoulder 16 by moving the sleeve down. Further movement is prevented by abutment of the shoulder around extension 54 with the boss 58, which also servesto center the lower end of the spring 50.

When the pressure impulseis relieved, the valve 26 immediately closes and the piston 30` moves upward under the force of the spring 50, the lubricant above the piston passing outwardly past the shoulder 16 and downwardly around the sleeve to the bottom of the casing 10. The liquid thus `displaced before the top of the piston 30 engages the shoulder 40 of the sleeve will be equal to the volume discharged during the discharge stroke. While this would ordinarily take place with an ordinary ball check valve at the inlet, I prefer to provide the cylinder valve 26 having slots at 27, requiring a small displacement before opening and ermitting a small displacement after closing. Thispositively assures free,- dom of the spring 50 to drawextension 54 out of the exit, w1thout`becoming hydrauli-I callly locked by the closing of the inlet check va ve.

Contact between the top of the istonO and the shoulder now re-establis es a mechanical connection between piston and sleeve and the parts move back together to the initial position of Figure 1 ready for the next cycle of operation.

It will be noted that at no time during the discharge stroke is there an open passa e through the device. On the return strole there will be an open passage during half the movement, but check valve 26 is closed at this time. If a new pressure impulse happened to arrive while the parts were moving back, the hydraulic pressure in the annular space under shoulder 40 would tend to separate the parts, and when they are'seperated as in Figure 2Ythere can never be an open passage through the device.

In the modification of Figure 6, the special valve 26 has been eliminated and a lain ball valve 66 substituted. Also the piston completes its seal considerably before the valve opens; i. e. there is no necessit for any accuracy in having the valve open simulat such a time open it again to let taneously with the completion of the seal by the piston'.

The valvev 32 may be identical with that of Figure 1 and the cap 16 except that it is cut away much less at the corner at 48 and forms a longer seal with the neck of the valve. The piston 68 enters inside a cup 7 0 in which it fits loosely enough to allow slow leakage, but contact o'f the outer edge 72. with the seat 74 makes a tight seal at the end of the stroke. Because the edge 72 has the full outside diameter of. the piston, movement after the seal is complete at does not change the space at 7 6 and itis immaterial whether the byass valve opens at tlie instant the seal is ormed or at some later point in the stroke. Spring 78 is preferably installed under heavy initial tension so that its pressure increases only slightly when the piston is pushed down. The substantially constant restorin cally eliminates the possibility of stopping the piston after it has completed half the return stroke and delivering a constant 'stream of lubricant to the part to be lubricated. Any pressure accidentally delivered dentally maintainedconstant at a precise value within narrow limits to avoid letting the piston move to'one end of its stroke or the other.

When pressure is relieved the leakage at 70 will let the annular seal at 72 open, at irst slowly, but much more rapidly as soon as an appreciable crack is open between the piston and its seat.

It will be noted that the -drawings show the parts enlarged to approximately four times their actual size for convenience of illustration.

Without further" elaboration the foregoing will so fully explain the gist of my invention, that others may, by applying currentlknowledge, readily adapt the same for vuse under various conditions of service.

Thus in Figure 5 I have illustrated a piston 60 corresponding to piston 30 but mounted directly in the receptacle l0 without any sleeve or other automatic control means. Such a system can be operated by simply valve 62 in a by-pass tube connecting the inlet of the chamber with the outlet, as indicated by the dotted line 64. Before pressure is delivered to the system it will be necessary to turn oil' valve 62, and after the pressure is relieved, it will be necessary to piston 60 return to its original position. These and many other modifications .and alterations may readily be made by those skilled in the art without eliminating certain features which may properly be said to constitute the essential items of novelty involved, which items are force praetiinstalling a manually operated wo'uldhave to be also acciing piston means,

intended to be defined and securedto me by the following claims:

I claim:

1. A lubricant measuring device comprising a body having an inlet and`an outlet, piston means normally subjected to the pressure of lubricant at the inlet, valve means arranged to by-pass said piston means, a lost motion connection betweensaid piston and said valve means whereby said valve Ameans will be opened upon a predetermined movement of said piston means, and` a spring biasing said piston toward one end of its stroke.

2. A lubricant measuring device comprisvalve means arranged to by-pass said piston means, a lost motion connection between said piston and said valve means, the degree of lost motion permitted by said connection being sli htly less than the length of the stroke of said piston means, and a spring biasing said piston toward the inlet end of its stroke, movement of said piston to the discharge end of its stroke opening said valve means.

3. .A lubricant measuring device comprising piston means, valve means arranged to by-pass said piston means, a lost motion connection between said piston and said valve means, and a spring biasing said piston toward one end of its stroke, said connection having vsuiiicient lost motion so that movement of said piston to the discharge end of its stroke will open said valve means, and movement to the inlet end will close said valve means. p

4. A lubricant measuring device comprising a casing having an inlet and an outlet, a piston element and a .by-pass valve element axially slidable in said casing, one of said elements being annular and encircling the other, a lost motion mechanical connection between said elements permitting the piston to have a greater travel than the valve, the piston being exposed lto the pressure of the incoming lubricant to move it toward the eXit, and resilient means pressing said piston away from said" eXit, said valve being shaped to open a path past said piston when moved toward the exit and to close said path when moved toward the inlet.

5. A lubricant measuring device comprising a casing having an inlet and an outlet, a piston element and a by-pass valve element axially slidable in said casing, said valve being annular and encircling said piston, a lost motion mechanical connection between said elements permitting the piston to have a greater travel than the valve, the piston being exposed to the pressure o the incoming lubricant to move it toward the exit, and resilient means pressing said piston away from'said exit, said valve being shaped to open a path past said piston when moved toward the exit and to closeY said path when moved toward the inlet.

6. A lubricant measuring device comprising a casing having an inlet and an outlet, a piston element and a by-pass valve element axially slidable in said casing, said valve being annular and encircling said piston, a lost motion mechanical connection between said elements permitting the piston to have Aa greater travel than the valve, the piston a sleeve valve axially slidable in said casing, a piston'slidable in said valve, a spring urging said piston toward said inlet, said sleeve valve having a shoulder abutting the inlet end of said piston, whereby pressure Huid delivered through said 'inlet tends to separatel said valve and said piston, friction means resisting movement of said valve with respect to said casing, and alost motion mechanical connection between said piston and said valve, said valve opening a path around said piston when moved toward vthe outlet and closing it when moved toward the inlet, said piston on movement toward the outlet closing said outlet before said valve. opens.

. `8. A lubricant measuring device comprislng a casing having an inlet and an outlet, piston means movable in said casing, said piston means having a central extension adapted to enter said exit and seal the same', a by-pass valve, and a lost motion connection between said by-pass valve and piston for opening said valve simultaneously with the closure of the exit by said piston.

9. A lubricant, measuring device comprismg. a casing vhaving an inlet and an outlet, a piston movable in said casing and adapted to enter said outlet and seal the same, said outlet having a portion of the full diameter of said'piston to receive the same, a by-pass valve, and ay lost motion connection between said by-pass valve and piston for opening said valve after said piston enters said .outletand before the end of the stroke.

10. A lubricant measuring device comprising a cylindrical chamber having one end thereof adapted to be connected to a bearing to be lubricated and the other end f thereof to a source of lubricant, a piston in said cylinder, a by-pass aroundsaid piston, a valve normally closing said toy-pass, and an operative connection between said piston and said valve to open said valve just prior to 'the completion of the operative stroke of said piston.

11. In a measuring device, a cylinder, an annularly grooved valve reciprocable there- 5 in, and a resilient expansible split ring held in the groove in said Valve and frictionally engaging the Walls of said cylinder, thereby to hold said valve stationary with respect to said Cylinder at any point in its stroke. 10 f In Witness whereof, I hereunto subscribe my name this 23 day of April, 1925.

' DONALD H; SWEET. l 

